Waterproof garment with invisible barrier seam

ABSTRACT

A waterproof invisible bather seam is formed between two fabric laminates, an outer shell fabric laminate and an inner lining fabric laminate. The seam includes an invisible seam tape that forms a hydrostatic bather within the seam. The design of the seam allows the formation of an effective hydrostatic barrier along the seams of a soft shell garment, while retaining flexibility, stretch, aesthetic appearance, and reversibility.

Priority is claimed to U.S. Provisional Application Ser. No. 61/297,477,entitled “Waterproof Garment With Invisible Barrier Seam”, filed on Jan.22, 2010, and to U.S. Provisional Application Ser. No. 61/301,366,entitled “Waterproof Garment With Invisible Barrier Seam”, filed on Feb.4, 2010. Both of said provisional applications are hereby incorporatedby reference in their entireties.

BACKGROUND OF THE INVENTION

The availability of waterproof or water resistant fabrics for outerwearpresents challenges to create seams that share the water sheddingcharacteristics of the fabrics. Laminated waterproof fabrics typicallycontain an outer face fabric of water repellant material, an innerinsulating fabric such as polar fleece, with a hydrostatic barriermaterial between the inner and outer fabrics. The use of laminatedfabrics containing a hydrostatic barrier material poses the problem ofhow to join the barrier material across a seam without introducing leakpathways. Existing methods of joining such fabrics to form a waterproofseam are unsatisfactory and commercially non-viable because they resultin a bulky, stiff, and unattractive seam; because they do not succeed infully merging the hydrostatic barrier across the seam; or because theyare difficult and time consuming to manufacture. Thus, there remains aneed for improved methods and seam designs for creating waterproof seamsfor outer garments and other textile products.

BRIEF SUMMARY OF THE INVENTION

The invention provides a hydrostatic or waterproof “invisible barrier”fabric seam, methods for making the seam, and garments or other productscontaining the seam.

One aspect of the invention is an invisible barrier fabric seam. Theseam is resistant to penetration by water or any of a variety ofchemical and/or biological agents. The properties of the seam rely onthe application of a seam tape that provides a hydrophobic polymermembrane within the seam and along the length of the seam. The seam tapeis invisible from both outer surfaces of the finished seam. Compared toprior water resistant or waterproof seams, the invisible barrier seam ismore flexible, more aesthetic in appearance, and results in a completelyreversible garment. Because the seam tape is protected within the seam,the invisible barrier seam is also more durable.

In still another aspect of the invention, an invisible barrier seam isformed by first making an outer garment and an inner garment and thenbonding the two garments together at the seams to form a single garment.The method includes the following steps: (1) The starting components formaking the seam are made or provided from a commercial source. Theseinclude an outer shell fabric laminate, an inner liner fabric, and abarrier seam tape. The outer shell fabric laminate contains a shellfabric laminated to a hydrophobic polymer membrane. In an alternativeembodiment the outer shell fabric laminate contains a polymerencapsulation layer. The seam tape contains a low melt adhesive filmlayer and a high melt barrier film layer such as a hydrophobic polymermembrane; optionally the seam tape also contains a release papercovering the adhesive layer and/or the barrier film. (2) Outer garmentpieces are cut out of the shell laminate according to an outer garmentpattern. (3) Inner garment pieces are cut out of the liner fabricaccording to an inner garment pattern, which has overlapping seamlocations compared to the outer garment pattern. (4) Each of the outerand inner garments is separately assembled. The seams of the outerand/or inner garments are initially formed using an ultrasonic weldoperation, by sewing, or by using a centerline adhesive film thatprovides a tack to hold the pieces together. (5) The adhesive layer ofthe seam tape is welded by heat or ultrasound onto the hydrophobicpolymer membrane surface of the shell fabric of the assembled outergarment. (6) The inner garment is then positioned inside of the outergarment and aligned. (7) The complete composite garment is assembled bywelding the seams of the inner garment to the seams of the outergarment; this is accomplished by applying heat or ultrasound energy tothe seams so that the low melt adhesive layer of the seam tape adheresto and seals the seam in the liner fabric along the length of the seam.In some embodiments an adhesive layer is present, either on the innerface of the liner fabric or on the inner face of the hydrophobic polymermembrane. The adhesive layer can then be heat- and/or pressure-activatedfollowing assembly of the composite garment in order to fix the innerand outer garments together over their full surfaces.

Another aspect of the invention is a method of forming an invisiblebarrier fabric seam. The method includes the following steps. (1) Threecomponents for making the seam are made, or provided from a commercialsource: an outer shell fabric laminate, an inner lining fabric laminate,and a seam tape. The shell fabric laminate includes an outer shellfabric which faces the outside of the final garment (ordinarily, theside facing away from the body of the wearer), a hydrophobic polymermembrane attached to the shell fabric, and optionally a lightweighttricot or scrim attached to the membrane. The liner fabric laminateincludes a liner fabric. An adhesive component or adhesive layer isoptionally attached to the liner fabric on the opposite side from theside facing the inside of the final garment or to the hydrophobicpolymer membrane of the shell laminate. The liner fabric is a fleece orother non-containable, preferably insulating fabric, and ordinarily isexposed at the inner surface of the garment facing towards the body ofthe wearer. If present in the liner laminate, the adhesive component iscapable of adhering to the shell fabric laminate, by adhering to thebarrier membrane or optional tricot/scrim. The seam tape contains anoptional inner low melt adhesive film layer which faces the lininglaminate in the finished seam, a high melt barrier film layer such as ahydrophobic polymer membrane, an exterior low melt adhesive layer whichfaces the shell laminate, and an optional release paper covering one orboth adhesive layers. The barrier film layer is disposed between theinner and outer adhesive layers. (2) The liner laminate is laminated tothe shell laminate to form a single, shell-liner composite laminate. (3)A pattern for two or more garment fabric pieces is then applied to theshell-liner laminate, and the pieces are cut out. (4) The pieces arethen placed together and aligned with the shell fabric sides facingtogether, so as to form a seam track along one edge of the alignedpieces. (5) The seam is initially formed using an ultrasonic weldoperation to connect the outer laminates, by sewing only the outer shelllaminates together, or by using a centerline adhesive film that providesa tack to hold the outer shell laminates together. (6) The edges of theadjacent liner fabrics, and of the optional tricot or scrim of the outerlaminate if present, and the seam tape is inserted into the seam betweenthe adhesive component of the liner laminate and the hydrophobic barriermembrane or tricot/scrim of the face laminate. (7) Heat or ultrasound isused to weld the barrier seam tape into position and to create ahydrostatic seal along the seam. (8) The liner fabric is then secured tocomplete the seam by heat welding using an adhesive film that holds theliner fabric in place.

Yet another aspect of the invention is a method of forming an invisiblebarrier fabric seam. The method includes the following steps. (1) Threecomponents for making the seam are made, or provided from a commercialsource: an outer shell fabric laminate, an inner lining fabric, and aseam tape. The shell fabric laminate includes an outer shell fabricwhich faces the outside of the final garment, a hydrophobic polymermembrane attached to the shell fabric, and a membrane-protective fabricsuch as a lightweight tricot or scrim attached to the membrane. Theliner fabric is a fleece or other non-containable, preferably insulatingfabric. The seam tape contains an inner low melt adhesive film layerwhich faces the lining fabric in the finished seam, a high melt barrierfilm layer such as a hydrophobic polymer membrane, an exterior low meltadhesive layer which faces the shell laminate, and optionally a releasepaper covering one or both adhesive layers. (2) A pattern for two ormore garment fabric pieces is then applied to the shell laminate andliner fabric, and the pieces are cut out. (3) The pieces are then placedtogether and aligned with the shell fabric sides facing together, so asto form a seam track along one edge of the aligned pieces. (4) The seamis initially formed using an ultrasonic weld operation to connect theshell laminates, by sewing only the shell laminates together, or byusing a centerline adhesive film that provides a tack to hold the outershell laminates together, while not restricting the inner lining frombeing folded back. (5) The edges of the adjacent liner fabrics arewithdrawn back from each side of the centerline of the seam, and theseam tape is inserted into the seam between the inner face of the linerfabric and the hydrophobic barrier membrane or tricot/scrim of the shelllaminate. (6) Heat or ultrasound is used to weld the barrier seam tapeinto position and to create a hydrostatic seal along the seam. (8) Theliner fabric is then folded back towards the centerline of the seam andheat welded to the remaining adhesive layer of the seam tape to completethe seam.

In another aspect of the invention, an invisible barrier seam is formedby first making an outer garment and an inner garment and then bondingthe two garments together to form a single laminated garment. The methodincludes the following steps: (1) The starting components for making theseam are made or provided from a commercial source. These include anouter shell fabric laminate, an inner liner fabric laminate, a barrierseam tape, and an adhesion layer attached to either the outer shelllaminate or the liner laminate. The outer shell fabric laminate containsa shell fabric laminated to a hydrophobic polymer membrane, or the outershell fabric laminate contains a polymer encapsulation layer. The linerfabric laminate includes a liner fabric. The seam tape contains an innerlow melt adhesive film layer and a high melt barrier film layer such asa hydrophobic polymer membrane, an optional exterior low melt adhesivelayer, and an optional release paper covering one or both adhesivelayers. (2) Outer garment pieces are cut out of the shell laminateaccording to an outer garment pattern. (3) Inner garment pieces are cutout of the liner laminate according to an inner garment pattern, whichhas one or more non-overlapping seam locations compared to thecorresponding seams in the outer garment pattern, though some of theseams can be overlapping. (4) Each of the outer and inner garments isseparately assembled. The seams of the outer and/or inner garments areinitially formed using an ultrasonic weld operation, by sewing, or byusing a centerline adhesive film that provides a tack to hold the piecestogether. (5) The seam tape is welded by heat, hot air, or ultrasoundonto the hydrophobic polymer membrane surface of the shell fabric of theassembled outer garment. (6) The inner garment is then positioned insideof the outer garment and aligned. (7) The complete garment assembly isthen subjected to an alignment lamination step by applying a heat and/orpressure source to the entire garment.

Yet another aspect of the invention is a method of assembling a garmenthaving multi-ply seams. The method includes the steps of: (1) preparingan outer garment having seams and an inner garment having seams thatmatch the position of the outer garment seams; (2) aligning one or moreseams in the outer garment with corresponding seams in the innergarment; (3) performing a soft-set adhesion of the outer and innergarments along the aligned seams, whereby the seams adhere together butremain adjustable; (4) adjusting the alignment of the outer and innergarments with respect to each other by loosening, moving, andreattaching the soft-set seams; and (5) performing a hard-set adhesionof the outer and inner garments along the aligned and adjusted seams toform a garment having one or more multi-ply seams. In some embodimentsthe outer garment contains an outer shell laminate having a shell fabricand a hydrophobic polymer membrane and the inner garment contains afleece or other non-containable, insulating fabric. In some embodimentsa seam tape is applied along the seam tracks between the outer and innergarments. In some embodiments the inner garment and/or the outer garmentincludes a layer of a heat-activated adhesive material that is used forthe soft-set and/or hard-set assembly steps.

Still another aspect of the invention is a method of forming aninvisible barrier seam using a single-ply seam tape. Pieces of an outershell laminate are joined along a seam track using ultrasonic welding toform a centerline bead a short distance from the edge of the fabrics.The shell laminate includes an outer shell fabric layer and ahydrophobic barrier membrane layer. The pieces are joined with the outershell fabrics facing each other. The centerline bead holds the fabricstogether. Flaps of the fabric from each piece protruding from thecenterline bead are folded back on the inside of the seam along the seamtrack, and a single-ply seam tape comprising an adhesive polymer isadhered across the inside of the seam, at least partially covering theflaps; the width of the seam tape can be less than the combined width ofthe flaps. Corresponding pieces of liner fabric are joined along a seamtrack using an ultrasonic cut-and-weld process that forms a centerlinebead and removes remaining loose fabric material, exposing thecenterline bead. The welded liner pieces are then positioned such thatthe centerline bead of the joined liner pieces is aligned along thecenterline bead of the joined shell laminate pieces. The seam is thenfused together by applying heat and/or pressure so as to set theadhesive polymer in the seam tape.

Another aspect of the invention is a method of forming an invisiblebarrier seam. In any of the foregoing methods, except embodiments thatinvolve sewing to form a seam, a string adhesive is included at the buttjoint between the two outer shell fabric pieces at the seam. When theseam is welded by heat or ultrasound energy, the adhesive material ofthe string adhesive melts and coats the cut edges of the shell fabrics,effectively sealing the edges and bonding the edges of the adjacentshell fabric pieces together. The result is a more robust and durableseam.

Still another aspect of the invention is a method of forming an outershell intermediate structure for an invisible barrier seam. Two-plyouter shell fabric pieces (each having a shell fabric layer and abarrier membrane layer) are aligned with the outer shell fabrics facingeach other, and ultrasonically welded together along the length of theseam at a short distance from the edge of the pieces. The free edges arethen folded over to lie flat against the barrier membrane. A barrierseam tape is adhered over the folded edges such that the barrier layerof the seam tape contacts the barrier membranes of both fabric piecesand forms a continuous barrier membrane layer across the seam.

Another aspect of the invention is a method of forming an inner linerintermediate structure for an invisible barrier seam. Two-ply innerliner fabric pieces (each having a liner fabric layer and an adhesivelayer) are aligned with the liner fabrics facing each other, andultrasonically welded together along the length of the seam at a shortdistance from the edge of the pieces. The free edges are then foldedover to lie flat against the adhesive layer. Optionally, a liner seamtape is then applied over the exposed edges and bonded to the adhesivelayer of the liner fabric pieces to strengthen the seam and/or to add anadditional permeability barrier along the seam.

Yet another aspect of the invention is a textile product, such as agarment, containing an invisible barrier fabric seam. In someembodiments, the garment as a whole is resistant or essentiallyimpervious to penetration by water. Some embodiments are alsoessentially impervious to penetration by any of a variety of chemicaland/or biological agents. Some such embodiments include an adsorbent forchemical and/or biological agents; the adsorbent is embedded within theliner fabric or added as an additional layer to the liner fabriclaminate or between the outer shell layer and the inner liner layer.Optionally, the assembled inner liner layer includes achemical/biological agent resistant seam tape having an adhesive layerand a fabric layer possessing and adsorbent for chemical and/orbiological agents. In certain embodiments, the textile product includesone or more insulation zones, each zone having a desired amount ofinsulating material, such as a fleece or other non-containable fabric,or an air bladder added between the outer shell layer and the innerliner layer. The insulation zones are selected to provide added warmthand comfort to selected areas of the body without restricting movementor adding weight.

Still another aspect of the invention is a seam tape for preparing aninvisible barrier seam. The seam tape includes an inner low meltadhesive film layer, a high melt barrier film layer, an optionalexterior low melt adhesive layer, and an optional release paper coveringone or both adhesive layers. The barrier film layer is disposed betweenthe inner and outer adhesive layers. In some embodiments, the seam tapealso contains a reinforcing fabric layer; the fabric layer is alsodisposed between the inner and outer adhesive layers, adjacent to eitherside of the barrier film layer.

Other features and advantages of the invention will be apparent from thefollowing description of the preferred embodiments thereof and from theclaims, taken in conjunction with the accompanying drawings.

BRIEF DESCRIPTION OF THE DRAWINGS

Other features and advantages of the invention will be apparent from thefollowing description of the preferred embodiments thereof and from theclaims, taken in conjunction with the accompanying drawings.

FIGS. 1A and 1B show schematic views of invisible barrier seamsaccording to the invention.

FIGS. 2A and 2B show schematic views of invisible barrier seams forembodiments having partial lamination between shell and lining.

FIGS. 3A and 3B depict cross-sectional views of embodiments ofintermediate structures in the formation of an invisible barrier seam.An outer shell seam intermediate structure is shown in FIG. 3A, and aninner liner intermediate structure is shown in FIG. 3B. FIG. 3C shows across sectional view of an embodiment of an invisible barrier seamhaving a single-ply seam tape.

DETAILED DESCRIPTION OF THE INVENTION

The invention provides an “invisible barrier seam” and methods formaking the seam, seam tapes, and garments or other textile productscontaining the seam. An invisible barrier seam according to theinvention creates a hydrostatic barrier between two pieces of waterproofor water resistant fabric. This is accomplished using a seam design thatallows a seam tape containing a hydrophobic polymer membrane to beadhered to the inner surfaces of an outer fabric and an inner fabricthat are joined at the seam. The result is a hydrostatically sealed seamstructure possessing a seam tape that cannot be seen from either theouter face or the inner face of the seam. The invisible barrier seam isespecially suited for joining laminated fabrics needed to make “shell”jackets and other outerwear, having a water resistant outer shell, anon-containable insulating inner lining fabric such as a fleece, and ahydrophobic polymer membrane between the shell and lining.

The term “non-containable fabric” as used herein refers to a fabric thatdoes not allow saturation of the spaces between fibers of the fabric byan adhesive to create a hydrostatic seal. A non-containable fabricgenerally has a large volume of open space between microfibers of thefabric. Examples of a non-containable fabric include fleece and otherinsulating materials.

A “fleece” as used herein refers to a pile fabric, including woolenfabrics as well as synthetic fabrics. Fleece for use in the inventioncan be made of or derived from natural fiber such as wool or a syntheticpolymer, such as polyethylene terephthalate (PET) (e.g., Polarfleece® byPolartec, LLC). Fleece is typically lightweight, insulating,hydrophobic, and breathable, i.e., allowing water vapor to pass through.Pile fabrics are made by dying loose fibers, which are then mixed andcombed into a long rope that is guided into a knitting machine, whichpermanently locks the fibers into a backing. The fabric is then shearedand finished. A pile results from the individual fibers standing on end.Fleece is made by first twisting fibers into a yarn, which is thenknitted into a fabric. The fabric is then brushed, sheared, andfinished.

An “insulating material” as used herein refers to a natural or syntheticmaterial that provides thermal insulation. Insulation for use in theinvention can be made of synthetic lofted continuous filament insulationsuch as Climashield® Apex by HarVest Consumer Insulation, or Thinsulate™microfibers by 3M. Insulating material is preferably lightweight andbreathable, and made from fibers that can be hydrophobic or hydrophilic,fire retardant, flexible, and obtained from recycling or from arenewable fiber. One or more layers of fabric, such as a fleece or othernon-containable fabric, or a tricot, can also be used as an insulatingmaterial.

Fabrics joined by a seam according to the invention, or created in theprocess of forming a seam according to the invention, can be laminatedfabrics or coated fabrics, and preferably are waterproof laminatedfabrics. A “laminated fabric” for use in the present invention or formedby a method of the present invention is a fabric that includes at leastthree layers: an outer layer containing a face fabric, an inner layercontaining a non-containable fabric such as fleece or another insulatingmaterial, and a middle layer disposed between the outer and inner layersand containing a hydrophobic polymer membrane. Additional layers mayalso be present, such as one or more support layers for the hydrophobicbarrier membrane and layers of adhesive between structural layers. A“coated fabric” or “encapsulated fabric” for use in the invention is afabric that has been coated with a chemical agent such as silicone,polyurethane, polyester, or polypropylene that coats the fabric andforms a liquid layer or a coating within the fabric, or on the surfaceof the fabric (such as the back surface of an outer shell fabric) thatserves the same function as a hydrophobic polymer membrane in alaminated fabric. Therefore, if a suitable encapsulated is used, forexample, as the outer shell fabric, then a hydrophobic polymer membraneof a fabric laminate can be optionally omitted. The fabric pieces joinedby a seam of the invention can be of identical or different materials,color, or texture, according to the design or other requirements of thegarment or textile product in which the seam is located.

A “hydrophobic polymer membrane” or “hydrostatic barrier membrane” asused herein refers to a layer of synthetic or natural polymers thatresists the passage of liquid water, in the form of droplets ormicrodroplets, across the membrane. Preferably, the hydrophobic polymermembrane allows the passage of water vapor, in the form of individualwater molecules, so as to promote breathability of the laminated fabric.A hydrophobic polymer membrane can be prepared from a material such asmicroporous or nanoporous polytetrafluoroethylene (PTFE), expanded PTFE(ePTFE), polyurethane, cross-linked polyurethane, polypropylene, orpolyester.

The outer shell or face fabric can be any fabric, but preferably ismechanically strong, abrasion resistant, and may also be waterrepellent. The face fabric can be, for example, a soft woven fabric, orany fabric woven or knit from one or more yarns of synthetic or naturalmaterial. Materials for the face fabric can include, for example,polyesters, polyamides, polyvinylchlorides, polyketones, polysulfones,polycarbonates, fluoropolymers, polyacrylates, polyurethanes,co-polyetheresters, polypropylenes, and co-polyetheramides. The facefabric can have any desired color and texture (e.g., it can have acamouflage pattern or it can be infrared or near-infrared absorptive orreflective), and can be dyed or impregnated as needed to achieve adesired appearance or functionality, such as water repellency (DWR). Theface fabric may contain Lycra® or another elastic fiber to createstretch characteristics. Lycra®, also known as spandex or elastane, is apolyurethane polyurea copolymer that can be woven into a fabric, such asa face our outer shell fabric, a liner fabric, or a seam tape fabric toprovide elasticity. Alternatively, elasticity or stretch can be providedby using a woven or non-woven fabric having stretch in at least onedirection. It is preferred that the face fabric, liner fabric, and anyseam tape fabric provide a similar or essentially identical degree ofstretch, for optimum comfort and non-restrictive feel of the garment.The fleece fabric can be any fleece, such as a fleece made of PET, andcan have any texture, color, or thickness as desired or as appropriatefor a particular garment. The fleece is preferably insulating,breathable, and soft to the touch. In addition to the outer, middle, andinner layers, other layers also can be included in a laminated fabricfor use in the invention. For example, one or more reinforcing layerscan be added to mechanically support the hydrophobic polymer membrane.Adhesives also can be added to join the layers of the fabric, andchemical substances such as flammability retarding agents can be added.

An example of a waterproof laminated fabric is Gore-Tex (see, e.g., U.S.Pat. No. 3,953,566), which utilizes a porous PTFE membrane as thehydrophobic polymer membrane. The PTFE membrane of a Gore-Tex fabric hasa microstructure characterized by nodes interconnected by fibrils. Themicroporous or nanoporous nature of the PTFE membrane is such that waterdroplets are excluded from the pores, whereas water molecules can passthrough the pores.

In some embodiments of the present invention a fabric, fabric laminate,or an entire garment or textile product is impermeable to chemicalagents and/or biological agents. Any known method for rendering a fabricimpermeable to such agents can be used. For example, an “active agent”as described in U.S. Published Patent Application 20070264203 can beembedded within or coated upon a hydrophobic polymer membrane, a linerfabric, a shell fabric, a seam tape, or an insulating material, where itserves to bind, entrap, and/or inactivate harmful chemical and/orbiological agents. Such active agents include, for example, activatedcarbon, activated aluminum oxide, silica gel, soda ash, aluminumtrihydrate, baking soda, p-methoxy-2-ethoxyethyl ester cinnamic acid,zinc oxide, zeolite, titanium dioxide, silver and silver compounds, andmolecular filter materials, any of which can be microsized or nanosized.

In certain embodiments the fabrics used can be fire resistant or fireretardant. This can be achieved by a variety of known mechanisms, suchas coating the fibers of the outer shell fabric, liner fabric, and/orseam tape with a fire resistant polymer, such as polyurethane, and anoil and water repellant composition, such as fluoroalkyl acrylatecopolymer and thiourea formaldehyde. See, e.g., U.S. Pat. No. 7,666,802.

A variety of textile products can utilize an invisible barrier seam ofthe present invention. Preferably, such textile products are garments orarticles of clothing, such as jackets, coats, parkas, raincoats, cloaks,ponchos, shirts, blouses, pants, shoes, boots, gloves, hats, hoods, orother headwear, or underwear such as undershirts, briefs, bras, socks,and diapers. Other textile products into which the invisible barrierseam can be incorporated include blankets, towels, sheets, pet bedding,tents, sleeping bags, tarps, boat covers, carpeting, rugs, mats, windowcoverings, and upholstery. The invisible barrier seam can also be usedin protective suits for handling of hazardous materials, includingchemicals, biological materials, and radioactive materials, or inprotective suits for firefighters, military personnel, and medicalpersonnel. The invisible barrier seam also can be used in anytextile-based structure or device that serves to entrap, store, ortransport water or an aqueous liquid, such as bags, hoses, or bladders.

A seam according to the invention can be assembled using an adhesivehydrostatic polymer. An “adhesive hydrostatic polymer” or “polymeradhesive” as used herein refers to a polymeric adhesive material orresin that forms a hydrostatic barrier against the membrane surface.Adhesive polymer resins can be selected for their adhesion properties,hydrophobicity or hydrophilicity, melting point, shear resistance,bonding/coating properties, washing and dry cleaning temperatureresistance, cleaning solvent resistance, high temperature resistance(e.g., ability to withstand autoclaving) chemical resistance, gasresistance, resistance to pathogens such as viruses and bacteria, aswell as ability to commingle with the laminated fabrics or theircomponents so as to create a hydrostatically sealed seam or a seam thatis resistant to chemical and/or biological agents. The seam tape wouldalso be designed to be stretchable to match the stretch characteristicsof the face fabric and inner liner laminates. Suitable adhesive polymerresins include, but are not limited to, polyurethanes, polypropylenes,polyamides, polyesters, and polyolefins. The adhesive hydrostaticpolymer can be cross-linked or non-cross-linked. The adhesive propertyof the adhesive hydrostatic polymer can be activated by heat, light,pressure, or chemical reaction, for example. Preferably, the adhesivehydrostatic polymer has a melting temperature that allows it to meltduring an application of ultrasonic energy, hot air, or another heatsource, and a viscosity in the melted state that allows it to flowthrough the seam structure, including any non-containable fabric, and beextruded out of the cut end of the seam during a cut/weld operationcarried out by an ultrasonic welding machine for fabric seam formation.Preferably the adhesive hydrostatic polymer is hydrophobic. In certainembodiments, the adhesive hydrostatic polymer is flexible and elasticenough to withstand active use of a garment containing the invisiblebarrier seam without breaking or forming leaks in the waterproof natureof the seam. In certain embodiments, the adhesive hydrostatic polymercan be solvent resistant, shear resistant, heat resistant, or resistantto microbial attack. In certain embodiments, two or more adhesivehydrostatic polymers can be used in the same seam structure. Forexample, an invisible seam tape according to the invention has an innerlayer of adhesive polymer and an outer layer of adhesive polymer. Ifdifferent adhesive layers are combined in a seam structure, then it canbe advantageous to select their melting temperatures as either about thesame, or different. Selection of different melting points can allowdifferent parts of the seam to be fused at different times and differenttemperatures. Different adhesive polymer layers used together in thesame seam tape or seam structure can differ in their melting points, forexample, by 5, 10, 15, 20, or more ° C.

An adhesive hydrostatic polymer can be supplied to construct a seamaccording to the invention in a variety of different forms. In apreferred embodiment the adhesive hydrostatic polymer is supplied in theform of a strip or tape that allows it to be conveniently applied alongthe length of the seam. Optionally, an automated adhesive tape feedingdevice can be used for this purpose. The shape and dimensions of anadhesive polymer strip can vary, but should be consistent with applyingthe adhesive polymer resin to the seam such that the resin becomesdistributed within the seam and fuses with the hydrostatic membranematerial of both fabric pieces along the length of the seam. One or moreadhesive strips can be used to make the seam, and the strips can befolded and oriented in different ways so that the adhesive resin flowsinto the seam structure and contacts the hydrostatic membranes of thefabric pieces.

Machines for performing cut/weld seaming operations using ultrasound areknown and commercially available. For example, the firm Jentschmann, AG(Huntwangen, Switzerland) provides a variety of suitable machines. Theultrasound energy applied during seaming can be adjusted according tothe needs of the particular seam, including the characteristics of thefabrics and the adhesive. Welding conditions depend on conditions oftemperature and humidity and the type of fabric, hydrostatic barriermembrane, and fleece. Ultrasonic machines are available which simplyweld fabrics together as well as those which cut fabrics in addition towelding them. Adjusting an ultrasonic fabric welding machine accordingto such conditions is well within the capabilities of the ordinaryskilled person. It is understood that an ultrasonic welding or cuttingand welding machine can be used to carry out methods of the invention indifferent modes. For example, an open area weld mode provides a thermalreaction between the ultrasound tool and the ultrasound sonotrode andthe fleece. A flat compression weld mode provides a thermal reactionbetween the ultrasound tool, the ultrasound cut/weld tool, and thefleece. This creates a flat fiber surface area, which allows a seam tapeto adhere to the edges left behind by an open area weld operation.

A seam according to the invention can be either straight or curved, andthe fabric pieces joined can have any shape or form as required for aparticular garment piece. Two or more pieces of fabric can be joined toform a seam.

In addition to ultrasound, other sources of energy that can be used toperform a seam welding operation for use in the invention include heatenergy, laser energy, and other forms of electromagnetic radiation(e.g., microwave or radio frequency).

Another seam forming operation which can be employed to prepare seamsaccording to the present invention involves the use of a centerlineadhesive film to hold the adjacent pieces together until a seam tape isapplied and heat-sealed to form the seam. The “centerline adhesive film”**** is a flexible, organic solvent resistant adhesive film in the formof a tape that can be applied to join the fabric pieces along the lengthof the seam. The centerline adhesive film contains either a single-facedor double-faced tack adhesive film. When applied across the edges of twopieces of fabric using a heat process (e.g., a hot iron or hot air gun),the centerline adhesive film holds them into position to create atemporary seam (e.g., a portion of an outer garment pattern). A seamtape can then be applied to the joined fabric pieces, and the adhesivesin the seam tape activated to provide a hydrostatic seal on the membranesurface of the outer shell laminate. In this manner, a strong seam isformed adhesively and without the use of ultrasound or sewing.

The hydrostatic resistance of an invisible barrier seam is not dependentupon driving the adhesives of a seam tape through the fabric surfaces tore-connect the hydrostatic membrane surfaces, as is required with priorart methods. Instead, the hydrostatic resistance of an invisible barrierseam is accomplished by directly attaching the seam tape to the membranesurface. While not intending to limit the invention to any particularmechanism, it appears that the hydrostatic resistance of an invisiblebarrier seam is accomplished by forming a continuous hydrophobic barrierthrough a thermal reaction of the adhesive film structures to connectthe membranes of the laminates and the membrane provided in the seamtape.

Several known methods are available for testing the hydrostaticresistance properties of a seam of the current invention. These includeASTM D 5385 Standard Test Method for Hydrostatic Pressure Resistance ofWaterproofing Membranes. Preferably, a seam according to the inventionhas a hydrostatic resistance of at least 1, 2, 3, 4, or 5 psi for 3minutes using ASTM D 5385. More preferably, a seam according to theinvention has a hydrostatic resistance of at least 3 psi for 3 minutesusing ASTM D 5385.

One embodiment of the invention is an “invisible barrier seam”. Theinvisible barrier seam is a multi-layer barrier film seam structure inwhich no seam tape is visible on either the front shell fabric surfaceor the inner liner fabric surface. Instead, a seam tape is positionedbetween the inner and outer fabrics. Referring to FIG. 1A, invisiblebarrier seam 100 is formed from outer shell laminate 15, inner lininglaminate 75, and invisible seam tape 55. The seam is formed at thejunction between shell fabric laminate pieces 2 and 4 and lining fabriclaminate pieces 6 and 8. The shell fabric laminate includes shell fabric10 to which is attached hydrophobic polymer membrane 20. In oneembodiment, the shell fabric laminate also includes an inner layer of amembrane protective fabric, such as a tricot or scrim 25 (see FIG. 1B).The lining fabric laminate includes lining fabric 70 and adhesive layer60. The seam tape includes hydrophobic barrier membrane layer 40, outeradhesive layer 30, and inner adhesive layer 50.

It is understood that an invisible barrier seam, as well as garmentscontaining such seams, can contain additional components, layers,pieces, additives, adhesives, or fabrics beyond those depicted inFIG. 1. For example, one or more additional insulating layers can beadded, or one or more additional seam tapes, particularly to cover anexterior surface of the seam. Adhesive layers can be applied either as acontinuous film or as a web of adhesive, or as a powder sprinkled overthe underlying surface. In a preferred embodiment, an insulatingmaterial is applied to the back surface (i.e., the face hidden withinthe garment) of the lining fabric (i.e., a fleece or othernon-containable fabric) by laminating the insulating material to thelining fabric via a web adhesive.

An “invisible seam tape”, “barrier seam tape”, “seam tape”, or“centerline adhesive seam tape” according to the invention is amulti-layered seam tape that possesses a hydrophobic polymer membraneand two adhesive layers. The term “multi-layered” means that the seamtape can be either 2-ply, 3-ply, or 4-ply. A 2-ply seam tape contains amembrane layer and a single low-melt adhesive layer on either side ofthe membrane. A 3-ply seam tape contains a membrane layer and twolow-melt adhesive layers, one on either side of the membrane. A 4-plyseam tape contains a membrane layer, a fabric layer on one side of themembrane, and two low-melt adhesive layers, one on the exposed side ofthe membrane and the other on the exposed side of the fabric. In anycase, either or both adhesive layers can optionally be covered by arelease paper layer. A 2-ply seam tape can be employed, for example, inembodiments where the liner laminate contains an adhesive layer, and theadhesive from the liner seals the side of the seam tape that lacks itsown adhesive. Any of the above described seam tape embodiments canfurther include an optional layer of an adhesive non-woven scrim or webadhesive (see below) attached to either or both of the adhesive layers.A web adhesive is a heat-activated adhesive that ensures optimum flowand penetration of the adhesive layer into fabrics, especiallynon-containable fabrics such as fleece. Thus, in a preferred embodiment,the seam tape includes a web adhesive layer on the side that will face afleece liner fabric.

The seam tape is designed to form a waterproof barrier within a seamaccording to the invention by the fusion of the seam tape membrane withthe membrane of the outer shell laminate mediated by a polymericadhesive that flows through the interior of the seam to physically andfunctionally join the two membranes. The seam tape includes an optionalinner low melt adhesive film layer, a high melt barrier film layer, anexterior low melt adhesive layer, and an option release paper coveringthe exposed surface of one or both adhesive layers. An embodiment ofsuch a seam tape is shown in FIG. 1A as structure 55. The barrier filmlayer has a higher melting point that that of either of the adhesivepolymer layers, so that the barrier film layer does not melt during seamformation. For example, the melting temperature of the barrier filmlayer can be, for example, 5, 10, 15, 20, 30, 40, or 50° C. or morehigher than the melting temperature of either or both of the inner andouter adhesive polymer layers. Optionally, the two low melt adhesivelayers can have differential low temperature melting points, or can havedifferent compositions (e.g., one could be cross-linked and the othernot cross-linked), allowing adhesion to be performed first on one sideof the seam tape at a lower temperature, then on the other at a highertemperature. Another embodiment of the seam tape is shown in FIG. 2B(structure 56). In this embodiment, the seam tape includes an additionallayer of a reinforcing fabric, such as a tricot, which is shown as layer45 in FIG. 2B.

FIG. 3 depicts two intermediate structures that are encountered incertain embodiments of a method of making an invisible barrier seamaccording to the invention. An intermediate structure 90 formed from anouter shell fabric laminate is shown in FIG. 3A. The laminate consistsof an outer shell fabric 10 laminated to a hydrophobic polymer membrane20. Two pieces of the laminate are shown to the left and right of thepartial seam structure, which is shown in cross section. The edges ofboth pieces have been folded over along the seam track such that theouter shell fabric is exposed along the inside face of the seam. Theintermediate can be fastened together by sewing or more preferably byusing an ultrasonic welding machine, which produces a centerline bead 80where the outer shell fabrics have been partially melted together. Thisprovides sufficient adhesion to hold the fabric pieces together untilseam tape 55 is adhered to cover the folded over pieces of the shellfabric laminate. Barrier seam tape 55 is adhered along the seam track byapplying heat and/or pressure. The seam tape forms a continuoushydrostatic barrier across the seam by the fusion of the hydrophobicpolymer membrane of the seam tape with the hydrophobic polymer membraneexposed beyond the edges of the folded-over shell laminate, thus forminga continuous hydrophobic polymer membrane across the seam.

Similarly, the liner intermediate structure 100 shown in FIG. 3B isformed by folding over the edges of the liner fabric 70. The linerfabric pieces can be joined by sewing or using an ultrasonic weldingmachine, which results in a centerline bead 85 that provides anadditional penetration barrier as well as providing adherence until aliner seam tape is applied. In some embodiments, such as that depictedin FIG. 3B, a liner seam tape 75 is then applied to cover thefolded-over edges of the liner fabric. A liner seam tape can be used toprovide additional hydrostatic resistance to the seam, or to provideadditional protection against chemical or biological agents. The linerseam tape can be similar or identical to the barrier seam tape appliedto the outer shell seam, e.g., to provide added hydrostatic resistance,or it can have additionally a layer of liner fabric or other fabrichaving adsorbents for chemical or biological agents. Preferably, theliner seam tape includes adhesive layer 50 and liner fabric layer 70, asdepicted in FIG. 3B.

FIG. 3C depicts the structure of an embodiment of an invisible barrierseam 110 formed from two intermediate seam structures using a single-plyseam tape. Pieces of an outer shell laminate are joined along a seamtrack using ultrasonic welding to form a centerline bead 80 a shortdistance from the edge of the fabrics. The shell laminate includes anouter shell fabric layer 10 and a hydrophobic barrier membrane layer 20.The pieces are joined with the outer shell fabrics facing each other.The centerline bead holds the fabrics together. Flaps of the fabric fromeach piece protruding from the centerline bead are folded back on theinside of the seam along the seam track, and a single-ply seam tape 51comprising an adhesive polymer is adhered across the inside of the seam,at least partially covering the flaps; the width of the seam tape can beless than the combined width of the flaps. Corresponding pieces of linerfabric 70 are joined along a seam track using an ultrasonic cut-and-weldprocess that forms a centerline bead 85 and removes remaining loosefabric material, exposing the centerline bead. The welded liner piecesare then positioned such that the centerline bead of the joined linerpieces is aligned along the centerline bead of the joined shell laminatepieces. The seam is then fused together by applying heat and/or pressureso as to set the adhesive polymer in the seam tape. This type of seam ishydrostatically resistant and is exceptionally thin and flexible, havinga clean and barely visible exterior appearance from both sides of thegarment.

Another embodiment is a method of making a more robust invisible batherseam. The method includes the following steps. First, a fabric packageis laminated using a conventional commercial lamination process toproduce a shell fabric laminate. Alternatively, a commercially availableshell fabric laminate may be provided. The shell fabric laminateincludes an outer shell fabric, a hydrophobic polymer membrane, andoptionally a lightweight tricot or scrim. Next, a liner fabric laminate(e.g., a fleece or other insulating, non-containable fabric) is preparedby laminating an adhesive component to a liner fabric such as a fleeceor other non-containable, preferably insulating fabric. The adhesivecomponent is selected so as to be capable of adhering to the shellfabric laminate. The adhesive component can be, for example, an adhesivenon-woven scrim, a dry adhesive film, a liquid adhesive, or a drypowdered scatter-coated adhesive layer. In some embodiments, the linerfabric laminate omits the adhesive layer (see FIG. 2A), because in suchembodiments the lining fabric will be laminated to the shell laminateonly at the seam, or at the seam and a portion of the lining fabric, butnot over the entire surface of the lining fabric. A multi-layer barrierseam film or seam tape is prepared by lamination and cutting it to adesired width for integration into the seam to form a waterproof barrierwithin the seam. Alternatively, the seam tape can be provided from acommercial source. The seam tape includes an optional inner low meltadhesive film layer, a high melt barrier film layer, an exterior lowmelt adhesive layer, and optional release paper covering one or bothadhesive layers.

The liner fabric laminate can be laminated to the shell fabric laminateto form a single, shell-liner composite laminate (see embodiments shownin FIGS. 1A, 1B). This process is carried out in such a manner as toallow the later separation of the adhesive layer and the liner fabricfrom the membrane or optional tricot/scrim package without damaging themembrane surface; this allows the seam tape to be inserted later withinthe seam. In order to assure that the laminates can be later separatedto introduce the seam tape, a limited amount of heat, pressure, and/orultrasound energy is applied during this lamination step, so that thebond between the shell laminate and liner laminate remains reversible.Later, after garment is complete, more energy can be applied so as torender the composite laminate irreversibly bonded together. In analternative embodiment, the liner fabric is not laminated to the shellfabric laminate (see embodiments shown in FIGS. 2A, 2B). In suchembodiments, the adhesive layer can be omitted from the lining fabric,and preferably a tricot/scrim layer (see structure 25 in FIGS. 2A and2B) is included in the shell fabric laminate to protect the barriermembrane layer (structure 20 in FIGS. 2A and 2B).

A pattern for two or more garment fabric pieces is then applied to theshell-liner laminate, and the pieces are cut out. The pieces are thenplaced together and aligned with the shell fabric sides facing together,so as to form a seam track along one edge of the aligned pieces. Oncealigned, the seam is initially formed, preferably using an ultrasoniccut and weld operation. Alternatively, the seam is initially formed bysewing the shell fabric laminates together, but not sewing the liningfabric laminates together. The joined fabric pieces are then unfolded sothat the interior liner fabric of both pieces is facing upwards. Next,in order to add the invisible barrier seam tape, the two edges of theliner fabric are peeled back from each side of the centerline of theseam. The multi-layer barrier seam tape is then inserted into the seambetween the adhesive component of the liner laminate and the hydrophobicbarrier membrane or tricot/scrim of the face laminate. Then, hot air orultrasound is used to weld the barrier seam tape into position and tocreate a hydrostatic seal along the seam, while the edges of the linerfabric are still peeled back. After the seam tape is welded intoposition, the paper backing of the seam tape can be peeled back toexpose the remaining adhesive film layer on the seam tape. After foldingback the two edges of the liner fabric towards the seam centerline, andto cover the seam tape, the liner fabric can be heat welded together tocomplete the seam.

The process described above is repeated for all the seams of thegarment, or at least for all the seams for which moisture resistance isdesired.

In yet another embodiment, an invisible barrier seam is produced byfirst making two entire garments, an inner garment and an outer garment,and then heat welding or sewing them together to form invisible barrierseams throughout the single resulting composite garment. First, the samethree starting components are made or provided as in the methoddescribed above: an outer shell fabric laminate, an inner liner fabriclaminate, and a barrier seam tape. The outer shell fabric laminatecontains a shell fabric laminated to a hydrophobic polymer membrane. Ifthe shell laminate and liner laminates are to be co-laminated throughoutthe garment, then preferably no additional layer is added on top of themembrane, as the membrane will be bonded directly to the lining fabriclaminate in the final garment. In that case, an adhesive layer isprovided either as the inner face of the liner laminate or as the innerface of the outer shell laminate (e.g., applied over the hydrophobicpolymer membrane on the side facing the liner). A preferred adhesivelayer is formed by applying a web adhesive material to either the linerlaminate or outer shell laminate. An example of a suitable web adhesiveis Bostik PE103 web adhesive (e.g., at 20-50 g/sq.yd.), which is anon-woven polyester-based hot melt adhesive that is activated by hot airor radiant heat at 105° C. or steam pressing. On the other hand, if theshell laminate and liner fabric are only to be joined at the seams, thenthe inclusion of a tricot/scrim layer in the shell laminate is highlypreferred, so as to protect the hydrophobic barrier membrane of theshell laminate. In a variation of this embodiment, the outer shellfabric laminate contains a polymer encapsulation layer on the insidesurface (or on both inside and outside surfaces) as an alternative tohaving a hydrophobic polymer membrane.

Next, outer garment pieces are cut out of the shell fabric laminateaccording to an outer garment pattern. According to an inner garmentpattern, which may or may not have non-overlapping seam locationscompared to the outer garment pattern, inner garment pieces are cut outfrom the lining fabric laminate. A mismatch of the outer and innerpatterns enables the inner garment (lining fabric), to serve as abacking fabric to the seam film of the outer garment (shell fabric),which not only provides resistance to moisture infiltration but alsoincreases the overall strength of the seam structure of the outergarment. Similarly, the outer garment (shell fabric) then serves as abacking to the inner garment, enhancing seam strength of the innergarment. Alternatively, if the inner and outer garments are to be fusedonly at the seams of the garment, then the seam locations of the innerand outer garments will preferably overlap.

After the pieces have been cut, each of the outer and inner garments isseparately assembled. A preferred assembly method is to ultrasonicallycut & weld the seams. An alternative method of assembly is to sew thepieces of the outer garment together and to separately sew the pieces ofthe inner garment together. Any conventional sewing method can be used.In this embodiment, there is no need to later open the seams to insertthe seam tape. Instead, the multi-layer barrier seam tape is welded byheat or ultrasound onto the hydrophobic polymer membrane surface of theshell fabric. This creates a continuous hydrostatic barrier across theseams of the outer garment. Another alternative method of assembly is touse an adhesive centerline seam tape to hold the adjacent pieces of eachof the inner and outer garments together, and then to heat-seal the seamtape to the inner face of the respective inner or outer garment. Whenapplied across the edges of two pieces of fabric, the centerlineadhesive seam tape holds them into position to create a temporary seam.The adhesives in the seam tape are heat activated to provide ahydrostatic seal on the membrane surface of the outer shell laminate.This technique can be especially useful in assembling the outer garment,since a seam tape will be applied to the outer garment anyway to sealthe seams. An advantage of using a centerline adhesive seam tape toassemble fabric pieces is that it can avoid the use of expensiveequipment such as an ultrasonic cutting and welding machine.

After the inner and outer garments have been assembled from theirrespective pattern pieces, the inner garment is positioned inside of theouter garment and the two garments are aligned. As a final step, thecomplete garment assembly, or any portion thereof, can be subjected toan alignment lamination step by applying a heat and/or pressure sourceover a large area of the assembled garment, or over the entire garmentat once. This final step of alignment lamination creates a stronglaminate bond between the two surface fabrics of the garment. An exampleof an appropriate heat and pressure source is the Dressman ironing robot(Siemens). To use such a robot, the garment is placed over the robot,which is then inflated to fit the garment from the inside, applyingpressure. The robot is then filled with heated air or steam, whichapplies heat to the entire garment. Alternatively, a conventional steamironing table could be used to carry out alignment lamination. Whencompleted, the garment is entirely waterproof, and because the seam tapeis hidden within the seam, the garment is also completely reversible. Ifa partial adhesive surface area is used on the inner garment (i.e., onthe lining fabric), then that surface area including the adhesive wouldbe subjected to an alignment lamination by applying heat and/or pressureto create the inner laminate. If an adhesive is not used on the linerfabric, and the liner fabric is anchored to the inner layer of the lowmelt adhesive contained on the seam tape surface, then that surface areamust be subjected to an alignment lamination or a similar processinvolving application of heat and/or pressure to essentially just thearea containing the seam tape, without the need to perform alignmentlamination over the entire garment. In the event that a polymerencapsulated shell fabric is used, care is taken to apply sufficientheat and/or pressure for sufficient time to cure the bond (i.e., to meltthe encapsulation polymer) between the shell fabric and the liningfabric laminate.

When an outer garment and an inner garment are assembled by adhesion ofthe seams of each garment to one another, a “multi-ply seam” is formed,consisting of an outer shell seam intermediate adhered to an inner linerseam intermediate. FIG. 3A shows an embodiment of an outer shell seamintermediate structure, and FIG. 3B shows an embodiment of an innerliner seam intermediate structure. The invention provides a method ofassembling a garment having multi-ply seams. First, an outer garment andan inner garment are assembled; one or more of the seams of the innergarment match the position of the outer garment seams. Next, one or moreseams in the outer garment are aligned with corresponding seams in theinner garment. A “soft-set adhesion” of the outer and inner garmentsalong the aligned seams is then carried out. In soft-set adhesion, thealigned seams are adhered together but remain adjustable. Soft-setadhesion can be carried out, for example by applying a limited amount ofheat and pressure (e.g., manually using a steam iron or a hot air gunfor several seconds, e.g. about 2-5 seconds, or about 5-10 seconds, orjust enough time, pressure, and/or heat to adhere the seams such thatthey still can be dissociated. The alignment of the outer and innergarments is then carried out with respect to each other by looseningindividual soft-set seams as required, moving the outer and innergarments with respect to each other as appropriate to improve theiralignment, and reattaching the soft-set seams to each other. Finally,once the outer and inner garment alignment is satisfactory, a “hard-setadhesion” of the outer and inner garments is performed along the alignedand adjusted seams to form a garment having one or more multi-ply seams.The hard-set adhesion process applies heat and/or pressure in greateramount or duration compared with the soft-set adhesion (e.g., greaterthan 5 seconds, greater than 10 seconds, or about 20-30 or more secondswith a steam iron or a hot air gun, or sufficient time, pressure, and/orheat to ensure an essentially permanent adhesion of the multi-ply seam).A multi-ply seam can be formed of any type of fabrics, and using anytype of intermediate seam structures. Preferably, the outer garmentcontains an outer shell laminate having a shell fabric and a hydrophobicpolymer membrane and the inner garment contains a fleece or othernon-containable, insulating fabric. A seam tape can be applied along theseam tracks between the outer and inner garments in order to reduce thepermeability of the seam to any desired penetrant, such as water,chemical agents, or biological agents. A seam tape also can be appliedbetween the inner and outer garments to render the seam more robust anddurable. If desired, the inner garment and/or the outer garment caninclude a layer of a heat-activated adhesive material facing the centerof the seam, such that the entire inner and outer garments can beadhered to each other.

In any of the previously described methods, except embodiments in whicha seam is sewn, an optional additional step is the inclusion of a stringadhesive on the outside face of the seam, between the adjacent edges ofthe outer shell fabrics joined at the seam. A string adhesive contains afiber, string, or thread, e.g., a cotton or synthetic polymer threadthat is coated with a polymer adhesive such as polyester, polypropylene,polyvinylidene fluoride, polyurethane, polyvinyl chloride, orpolyethylene. See, for example, products of EY Technologies (Fall River,Mass.). Preferably, the diameter of the string is about the same as thethickness of the outer face fabric. The string adhesive can be addedjust before or after initially forming the seam, or as a final finishingstep. The string adhesive can also be supplied pre-adhered at thecenterline of a seam tape; in use, the string would be aligned with thecenterline of the seam, so that a butt seam is formed between the piecesof outer face fabric, with the string remaining between the fabricedges. The string adhesive is placed into the region where the two outershell fabrics come together at the seam prior to a step of applying heator ultrasound to seal the seam. When the seam is welded by heat orultrasound energy, the adhesive of the string adhesive melts and coatsthe cut edges of the shell fabrics, effectively sealing the edges andbonding the edges together. The result is a more robust and durableseam.

The methods, seams, and seam tape described herein can be utilized inthe production of outerwear garments, such as waterproof jackets, coats,and suits of any design. A garment product produced using any of themethods, seams, or seam tapes according to the invention can be used,for example, either as a liner for an outer shell assembly or as astand-alone product. Other garments that can be produced using themethods and seams of the present invention include pants, gloves, hats,socks, and protective suits. The methods and seams of the invention canalso be used in any textile product or any product containing a seambetween two fabric pieces, including footwear (e.g., shoes, boots),tents, and other products. Seam structure and seam tape can be providedin different widths, such as in widths of 6 mm, 8 mm, or 10 mm or wider.Alternatively, the seam structure is a butt seam and has no nominalwidth. The methods described herein can be carried out manually or usingautomation, or any combination thereof.

The present invention makes possible a new type of soft shell fleece orhard shell insulated waterproof jacket. Using previous technologies,soft shell jackets could be made of a waterproof fabric, such as alaminate containing a hydrostatic barrier membrane, but they would leakthrough any welded or sewn seams. Previous waterproof seam designsplaced a seam tape on the interior of the jacket, where the fleece orinsulating material had to be shaved down in order to reach thehydrostatic barrier membrane, resulting in an awkward and slowmanufacturing process. This would also result in loss of insulationvalue at the seam. With the present seam design, however, no seam tapeis required on the inner fleece side of the seam, and there is little orno loss of insulation at the seam. Further, no seam tape is required onthe exterior of the jacket, and the jacket can be made completelyreversible without any visible seam tape or impression of a seam tapefrom either side. Seams according to the present invention also can bemade smaller, more flexible, and more comfortable than earlier designsfor waterproof seams. Soft shell jackets according to the presentinvention also have superior properties compared to previously knownhard shell jackets featuring waterproof seams. The present seam designpermits the insulating material to be placed on the inside of thejacket, and yet still permits the hydrostatic barrier membranes of thelaminated fabric to be joined within the seam and to connect through theseam.

As used herein, “consisting essentially of” does not exclude materialsor steps that do not materially affect the basic and novelcharacteristics of the claim. Any recitation herein of the term“comprising”, particularly in a description of components of acomposition or in a description of elements of a device, can beexchanged with “consisting essentially of” or “consisting of”.

Other embodiments of the invention will be apparent to those skilled inthe art from a consideration of this specification or practice of theinvention disclosed herein. It is intended that the specification andthe examples be considered as exemplary only, with the true scope andspirit of the invention being indicated by the following claims.

What is claimed is:
 1. A method of making a garment comprising an invisible barrier fabric seam, the method comprising the steps of: (a) providing an outer shell fabric laminate, an inner liner fabric, and a seam tape, the outer shell fabric laminate comprising a shell fabric and a hydrophobic polymer membrane, and the seam tape comprising an adhesive layer and a hydrophobic polymer membrane, wherein the hydrophobic polymer membrane of the seam tape is disposed adjacent to the adhesive layer; (b) cutting a plurality of outer garment pieces from the outer shell fabric laminate according to an outer garment pattern; (c) cutting a plurality of inner garment pieces from the inner liner fabric according to an inner garment pattern; wherein seam locations of the inner garment pattern overlap with seam locations of the outer garment pattern; (d) assembling one or more seams of an inner garment from the inner garment pieces and assembling one or more seams of an outer garment from the outer garment pieces; (e) attaching the seam tape to the outer shell fabric laminate along one or more of the assembled seams of the outer garment using heat or ultrasound energy, whereby the adhesive layer of the seam tape adheres to the hydrophobic polymer membrane of the outer shell fabric laminate; (f) aligning one or more of the assembled seams of the inner garment inside of the outer garment to form a composite garment, whereby the assembled seams of the inner garment are aligned with the seam tape attached to the outer garment; and (g) applying heat and/or pressure to one or more seams of the composite garment so as to seal the seams of the garment and join the inner and outer garments at one or more seams.
 2. The method of claim 1, wherein the liner fabric further comprises an adhesive layer.
 3. The method of claim 1, wherein the shell fabric laminate further comprises an adhesive layer in contact with the hydrophobic polymer membrane on the side opposite the shell fabric.
 4. The method of claim 1, wherein step (g) includes the following steps: (g1) applying limited heat and/or pressure to the seams to produce soft-set seams having reversible adhesion; (g2) adjusting the alignment of the outer and inner garments by loosening and realigning the soft-set seams; and (g3) applying greater heat and/or pressure than in (g1) to the seams to produce hard-set seams having long-lasting adhesion.
 5. The method of claim 4, wherein the inner garment is smaller than the outer garment, and the inner garment is stretched to fit snugly against the outer garment in step (g2).
 6. The method of claim 1, further comprising: (h) applying heat and/or pressure to the composite garment to adhere the outer shell fabric laminate to the inner liner fabric. 